code: def tearDownClass(cls) -> None:
      ray.shutdown()
  
file_path: ray/rllib_contrib/simple_q/tests/test_simple_q.py
imports: import unittest
  import numpy
  import rllib_simple_q.simple_q.simple_q
  from rllib_simple_q.simple_q.simple_q_tf_policy import SimpleQTF2Policy
  from rllib_simple_q.simple_q.simple_q_torch_policy import SimpleQTorchPolicy
  import ray
  from ray.rllib.policy.sample_batch import SampleBatch
  from ray.rllib.utils.framework import try_import_tf
  from ray.rllib.utils.metrics.learner_info import DEFAULT_POLICY_ID, LEARNER_INFO, LEARNER_STATS_KEY
  from ray.rllib.utils.numpy import fc, huber_loss, one_hot
  from ray.rllib.utils.test_utils import check, check_compute_single_action, check_train_results, framework_iterator
label_desc: Use image node_id 2 for calling the TestSimpleQ obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types